Prof. P. M. Duncan on the Genus Hindia. 227 



contest with Prof. Steinmann any further. But two points of 

 considerable interest have been raised by Dr. Rauff and by 

 my friend Dr. Hinde, who first of all brought the fossil under 

 my notice. 



Firstly, I called the species Hindia sphceroidalis^ and 

 described it so that Dr. liauff had no difficulty in recog- 

 nizing the form ; the morphology of the species and its special 

 characters were also given by me (Ann. & Mag. Nat. Hist. 

 ser. 5, vol. iv. p. 91). But Dr. Hinde, in the admirable 

 ' Catalogue of Fossil Sponges in the British Museum/ p. 57, 

 1883, replaces my name '•'' sphceroidalis'''' by ^' Jibrosa,^^ and 

 attributes the species to Ferd. Roemer. I demur to this 

 proceeding, and for the following reasons : — It is a rule in 

 classification that a species, in order to be established, must 

 be so described that other forms than the type can be recog- 

 nized. Subsequently, however, the generic name may be 

 altered, and the species always remains with the describer'a 

 name attached. Now Ferd. Roemer, in his ' Silurian Fauna 

 of W. Tennesse,' p. 20, described the form under consideration 

 as Calamopora fibrosa^ Goldf., and gave Favosites fibrosa^ 

 Lonsdale, as a synonym. He considered the form a coral, 

 and I maintain that there is not a single sentence in the 

 description, meagre as it is, that would lead any one to dis- 

 tinguish the form I described from New Brunswick as 

 belonging to it. So far as my recollection carries me, I passed 

 by Ferd, Roemer's description and figures as not relating to 

 the fossil I was then studying. Ferd. Roemer not having 

 properly and practically described the form he studied, and 

 having placed it amongst the Corals, I do not consider his 

 species of any value whatever. 



I cannot agree therefore to have my specific name 

 " sjyhceroidalis^' replaced by the unrecognizable and imper- 

 fectly-described " Jibrosa." I therefore restore the name I 

 gave to the sponge, and cannot recognize H. fibrosa^ F. 

 Roemer, sp. Hindia sphceroidalis^ Dune, is quite correct. 



The second point refers to the original mineralogical con- 

 dition of the New Brunswick specimen, and which Dr. Rauff 

 has examined at Munich. The present mineralization of the 

 tetraclade spicules is calcareous. Dr. Plinde {op. cit. p. 58) 

 writes : — " The examples from New Brunswick, however, 

 have had their original skeleton replaced by calcite ; and this 

 fact led Prof. Duncan to believe that they were originally 

 calcareous, so that ' there must have been a former mimetic and 

 calcareous group of Spotigida.^ " The last part of the sen- 

 tence is of coutse from my work. 



it was not, however, the calcareous nature of the spicules 



